Remove CS3-style initialization.

Remove libcs3-related bits from support/ld. Break them out into
libmaple proper and Wirish as appropriate: vector table definition and
ISR declarations go into libmaple proper, and startup code goes into
Wirish. Vector table symbols are included into common.inc from an
STM32 family-specific directory under support/ld/stm32.

This is a combination of 5 commits. Individual commit messages follow:

libcs3_stm32_src: Don't depend on cs3.h.

So we can use the existing toolchain.

Move ISR decls/vector table into libmaple proper.

This allows us to configure the vector table on a per-family basis.

- Move
        support/ld/libcs3_stm32_src/stm32_isrs.S
                                    stm32_vector_table.S
  to
        libmaple/stm32f1/isrs_performance.S
                         vector_table_performance.S,
  respectively.

  The directory libmaple/stm32f1/ is intended to hold all
  STM32F1-specific code within libmaple. Obviously, there's a lot of
  work to do before this becomes true.

- support/ld/libcs3_stm32_src/Makefile: Don't try to compile
  stm32_isrs.S and stm32_vector_table.S anymore.

- Add libmaple/stm32f1/rules.mk to include these new files in the
  standard libmaple build.

- support/make/target-config.mk: Add LIBMAPLE_MODULE_FAMILY, which
  selects a directory to use as a family-specific libmaple
  submodule.

- Makefile: Add LIBMAPLE_MODULE_FAMILY to LIBMAPLE_MODULES.

Remove support/ld/libcs3_stm32_src and derived object files.

From support/ld/libcs3_stm32_src, move start.S and start_c.c into
Wirish. Modify wirish/rules.mk accordingly.

Delete support/ld/libcs3_stm32_*_density.a. These are no longer
necessary, as the relevant objects are included in the standard Wirish
build. Remove the GROUP statements from the board linker scripts
accordingly.

Remove SEARCH_DIR(.) from common.inc; it's no longer necessary. Also
fix up some comments that are now out of date.

wirish/start_c.c: Don't use CS3-style memory initialization.

Switch memory initialization to a simpler style of initializing .data
if necessary, then zeroing .bss. Initializing .data is only necessary
during Flash builds, since during RAM builds, LOADADDR(.data) ==
ADDR(.data).

This makes libmaple completely incompatible with the CS3 startup
sequence. Subsequent commits will clean up the namespace to reflect
that fact.

Signed-off-by: Marti Bolivar <mbolivar@leaflabs.com>

1 files changed, 16 insertions, 32 deletions

diff --git a/support/ld/common.inc b/support/ld/common.inc
index c6fa13a..0d1f4ed 100644
--- a/support/ld/common.inc
+++ b/support/ld/common.inc
@@ -6,7 +6,6 @@
 
 OUTPUT_FORMAT ("elf32-littlearm", "elf32-bigarm", "elf32-littlearm")
 ENTRY(_start)
-SEARCH_DIR(.)
 
 /*
  * Link against libgcc, libc, and libm
@@ -22,10 +21,10 @@ GROUP(libgcc.a libc.a libm.a)
  */
 INCLUDE vector_symbols.inc
 
-/* STM32 vector table. See stm32_vector_table.S  */
+/* STM32 vector table. */
 EXTERN(__cs3_stm32_vector_table)
 
-/* libcs3 C start function. See cs3.h */
+/* libcs3 C start function. */
 EXTERN(__cs3_start_c)
 
 /* main entry point */
@@ -33,9 +32,9 @@ EXTERN(main)
 
 /* Initial stack pointer value. */
 EXTERN(__cs3_stack)
-PROVIDE(__cs3_stack = __cs3_region_start_ram + LENGTH(ram));
+PROVIDE(__cs3_stack = ORIGIN(ram) + LENGTH(ram));
 
-/* Reset vector and chip reset entry point. See start.S */
+/* Reset vector and chip reset entry point */
 EXTERN(_start)
 PROVIDE(__cs3_reset = _start);
 
@@ -48,7 +47,7 @@ SECTIONS
     /* TODO pull out rodata and stick into separate sections  */
     .text :
       {
-        __text_start = .;
+        _text = .;
         /*
          * STM32 vector table.  Leave this here.  Yes, really.
          */
@@ -100,17 +99,6 @@ SECTIONS
         KEEP (*(EXCLUDE_FILE (*crtend.o) .dtors))
         KEEP (*(SORT(.dtors.*)))
         KEEP (*crtend.o(.dtors))
-
-        /*
-         * struct __cs3_region used during __cs3_start_c
-         */
-        . = ALIGN(4);
-        __cs3_regions = .;
-        LONG (0)                          /* flags */
-        LONG (__cs3_region_init_ram)      /* initial contents */
-        LONG (__cs3_region_start_ram)     /* start address */
-        LONG (__cs3_region_init_size_ram) /* size of initial data */
-        LONG (__cs3_region_zero_size_ram) /* additional size to be zeroed */
       } > REGION_TEXT
 
     /*
@@ -119,6 +107,11 @@ SECTIONS
     .rodata :
       {
         *(.rodata .rodata.* .gnu.linkonce.r.*)
+
+        /* ROM image configuration; for C startup */
+        . = ALIGN(4);
+        _lm_rom_img_cfgp = .;
+        LONG(LOADADDR(.data));
       } > REGION_RODATA
 
     /*
@@ -153,7 +146,8 @@ SECTIONS
      */
     .data :
       {
-        __cs3_region_start_ram = DEFINED(_FLASH_BUILD) ? . : __text_start;
+        . = ALIGN(8);
+        _data = .;
 
         *(.got.plt) *(.got)
         *(.data .data.* .gnu.linkonce.d.*)
@@ -178,26 +172,16 @@ SECTIONS
      */
     .bss :
       {
+        . = ALIGN(8);
+        _bss = .;
         *(.bss .bss.* .gnu.linkonce.b.*)
         *(COMMON)
         . = ALIGN (8);
-        _end = .;
+        _ebss = .;
+        _end = _ebss;
       } > REGION_BSS AT> REGION_TEXT
 
     /*
-     * Constants needed for the pieces of CS3 we use during
-     * board startup; see libcs3_stm32_src/.
-     */
-    __cs3_region_init_ram = (DEFINED(_FLASH_BUILD) ?
-                             LOADADDR(.data) :
-                             LOADADDR(.text));
-    __cs3_region_init_size_ram = (DEFINED(_FLASH_BUILD) ?
-                                  _edata - ADDR(.data) :
-                                  _edata - ADDR(.text));
-    __cs3_region_zero_size_ram = _end - _edata;
-    __cs3_region_num = 1;
-
-    /*
      * Debugging sections
      */
     .stab 0 (NOLOAD) : { *(.stab) }